Solid, sustainable engineering student design

Students Miles Tryon-Petith, Patrick Stoddard, Alexander Klintworth and Wally Graeber view vegetables grown in the aquaponics display in the Town Center of the Wisconsin Institutes for Discovery. It's one of several such displays the students plan to assemble.

Giri Venkataramanan often finds his email inbox is a clearinghouse for interesting community problems: a monitoring device for use of “little free libraries,” or a small wind turbine for the roof of a veteran’s home. “They just keep coming in,” says Venkataramanan, a professor of electrical and computer engineering.

While many don’t fit into established courses, the professor knows they could offer interested students a challenge to think outside the traditional boundaries of electrical and computer engineering. So Venkataramanan recruited eight students—freshmen all the way up to fifth-year seniors—looking for hands-on engineering opportunities­, and gave them a chance to tackle projects of their choosing, with an emphasis on design related to sustainable living.

“The idea is that we’d be like consultants,” says Venkataramanan. “Electrical engineering has applications in so many different areas, that the potential for different projects here is pretty huge.”

That freedom led the students to some interesting places. Calvin Cherry, an electrical engineering senior returning in fall 2013 as a graduate student, explored how to quantify the ways that Madison residents could save money by shifting their energy use to times of day when electricity is the cheapest to produce. Another student—senior Andy Bose—worked on a design for a small, all-electric tractor for use at the Troy Gardens community farm in Madison, adopting an open-source design and optimizing its battery and electric drive systems. He’s even exploring the idea of a pedal-powered tractor. “It’s possible that given their needs, one really athletic person could just pedal for 20 minutes,” says Bose.

Three freshmen in the course even struck up an campus collaboration with the UW-Madison Office of Sustainability, working to expand the scope of a project to build small-scale aquaponic units, where fish waste can feed plants grown in water. Miles Tryon-Petith, a freshman intending to major in geological engineering and intern for the Office of Sustainability, teamed up with fellow intern and landscape architecture senior Wally Graeber to build a system that uses bacteria to convert the ammonia of fish waste into nitrites, and the nitrites into plant-sustaining nitrates. That allows the tank to be used to grow food—in this case, four kinds of lettuce, dill, swiss chard, two kinds of basil and marigold. “We’re making as close to a closed-loop system as we can,” says Tryon-Petith. “It’s mainly a way to grow vegetables, and fish are just along for the ride, helping us out in doing that.”

Growing a garden indoors under artificial lighting can be complex; Tryon-Petith and Graeber spend a lot of time monitoring nitrate levels, pH and water levels at the aquaponics display in the lobby of the Wisconsin Institutes for Discovery. But in the design group, Tryon-Petith recruited freshmen Patrick Stoddard and Alexander Klintworth, electrical engineering majors who worked to design a lighting control system using a Raspberry Pi, a cheap hobbyist computer that could be embedded in future aquaponic systems. Tryon-Petith says that remote lighting control—and eventually, remote measurements of the overall health of the system—will make broader rollout of aquaponics displays to future sites like the Madison Children’s Museum much easier to manage. “Right now, it’s mostly through human observation and maintenance, but as we move forward, it would be cool to make everyone’s life easier with automated monitoring networks,” he says. Someday, the team envisions multiple aquaponics units across Madison, linked together in a sort of “living network” that can talk to one another over the web.

Miles and his team share an infectious enthusiasm for sustainable engineering, a spirit that flows from students who get to work on a personally meaningful design project so early in their engineering careers. “Being able to integrate myself into an environment where I’m immersed in sustainable engineering has done loads to help me learn more from the experience,” says Tryon-Petith.

Their experience reflects everything Venkataramanan had hoped for: an early chance to work on real problems that require interdisciplinary thinking. “We’re hoping that in the next year, we’ll have an even bigger class with a larger group of engineering students, engaging with all the other engineering disciplines,” he says.